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17.5 brushless and 27 brushed - same or different?

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Old 10-24-2008, 07:48 AM
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Default 17.5 brushless and 27 brushed - same or different?

What are racers thoughts when mixed? Same, or is one better...
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Old 10-24-2008, 08:16 AM
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at our track (www.michianarc.com - 36x60 track size) we mix 17.5 and 27t in the 12th scale class. I think the 27t is just a hair faster, but both "parties" would have to drive perfect lines to see it.

That being said...

in our truck class (stadium trucks on carpted "offroad" track w/jumps and bumps) there is very little difference between 13.5 and 27T.

And that being said..
when we go outside to larger tracks 13.5 beats 27T all day long. I personally, havn't tested 17.5 to 27T on a larger track to see what the difference would be.
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Old 10-24-2008, 08:37 AM
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Originally Posted by RCThunder
What are racers thoughts when mixed? Same, or is one better...
I guess the easy answer is to look at the USVTA and it's power plant options, the actual answer is different to each individual track scenerio.

A good motor builder will get his 27T faster than the 17.5, but depending on your layout the 17.5 has the advantage on a tight technical infield section due to it's added torque, the 27T has the advantage on fast flowing and open designs.

Case in point, at a regional series event here in the midwest, a 27T TQ'd and won over the 17.5's. The driver built a great motor, drove clean, fast lines and it showed.

Each motor though, will have advantages and disadvantages, based on the track you are running on.
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Old 10-24-2008, 09:18 AM
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they still make and sell stock brushed motors?
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Old 10-24-2008, 09:25 AM
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The problem in compairing brushed to brushless is that thay give power/torque in different ways. But in general on a big fast open track the 27T will be a touch faster and on a tight technical track the torque provided by the brushless will have the advantage. That has been my experience in on-road applications
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Old 10-24-2008, 10:49 AM
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Originally Posted by Mason
they still make and sell stock brushed motors?
yes, and they still will until BL can win a big stock race. IMO, brushed is still faster, provided you have a properly tuned stock motor that is well maintained. For the average joe, BL will be faster, because you wont need to do any maintinence.

to the original poster - the performance between the two is very close, so its up to you with what you wanna go with - slight edge for lots of maintinence, or a tick slower, and no maintinence
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Old 10-24-2008, 12:03 PM
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Originally Posted by geeunit1014
yes, and they still will until BL can win a big stock race. IMO, brushed is still faster, provided you have a properly tuned stock motor that is well maintained. For the average joe, BL will be faster, because you wont need to do any maintinence.

to the original poster - the performance between the two is very close, so its up to you with what you wanna go with - slight edge for lots of maintinence, or a tick slower, and no maintinence
I agree. I have run both and find that they are pretty much equal with a slight (very slight) advantage going to the brushed motor as long as you can keep it maintained and tuned.
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Old 10-24-2008, 12:24 PM
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My thoughts are running the lower maintenance brushless 17.5 allows me more wheel time to improve my line and shave the precious tenths that might be made by the motor difference or time to work on car setup to squeeze out a bit more performance. It's all give and take to me...
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Old 10-24-2008, 01:33 PM
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Another thing is the battery choice my son and I both run an Xray 007, he ran 17.5 and lipo while I was running 27 brushed with nimh batteries. My car was just slightly faster, but now I have switched to a lipo battery and we seem to have the same speed based on lap times with me still running the 27 turn motor.
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Old 10-24-2008, 02:51 PM
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27T is faster but 17.5 is easier.
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Old 10-24-2008, 03:13 PM
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Brushed is definatly faster in TC on carpet. Me and one other guy qualified in the B at the Nats in Omaha, all the rest were CO27's. I wish I had run brushed then, I might have been able to squeek into the A. In my experiance with both, the brushed is about .2-.5 sec faster per lap till about the last 15-30 secs of the race, then they go about equal.
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Old 10-24-2008, 03:29 PM
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Our club is running 27t and 17.5 together this season in 12th scale, hope it's a good choice.
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Old 10-24-2008, 04:40 PM
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Tuning a motor helps a bunch on the 27T. The common denominator of the two 17.5 & 27T is the battery!
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Old 10-24-2008, 06:59 PM
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Mike,

ALL of the testing we did with the 17.5 for NOVAK last year had pretty similar results to what I'm reading here.

Using LIKE batteries with both

4 cell STOCK vs 4 cell 17.5 - STOCK was a bit faster on the OVAL
6 cell STOCK vs 6 cell 17.5 TOURING - stock was a bit faster on the On-Road. I don't think we ever got the TC's geared to max capacity at that time...in part due to the limited gears that were available then. (Plus one of the TC's was a TC3 and they are such a BiXch to gear change anyway.

The old HPI Pro2 didn't have any problem finding speed - or gear ratios.

Pretty much the same result with the LIPO testing.

The 17.5 speeds were close in most cases...but looked like when combined against somebody with a GOOD STOCK Motor tuning ability - the 27t had the advantage. When MOTOR Tuners were OUT of the picture - of course the results were closer.

We never tested anything in the OFF-ROAD stuff - but I did have a few guys do some testing just to see if that could be a decent speed for a slower stock class for entry level. Some liked it - some didn't.
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Old 10-24-2008, 08:16 PM
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a brushed 27t motor is 2 tenths a lap faster than a 17.5
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